Monitoring of chronically ill patients in the home environment will become more common in the near future as the population ages, health care costs increase and patients demand more control over their own care. The clinical data collected in the home, such as blood pressure, weight, and heart rate can be transmitted back to a caseworker or clinician who can provide early intervention to prevent re-hospitalizations. Many of the patients with chronic illnesses could benefit from home cardiac monitoring.
One very typical and dangerous arrhythmia is atrial fibrillation (AFIB). AFIB is the most common cardiac arrhythmia resulting in hospitalization in the United States. AFIB is identified by irregular heart rhythms and is clinically defined as uncoordinated contractions of the atria. Patients often experience palpitations and have an increased risk of stroke. Some patients may be asymptomatic. Approximately one-third of all strokes are due to AFIB. Furthermore, the presence of AFIB makes strokes 5-times more likely and 2-times more debilitating.
AFIB requires aggressive treatment. The longer a patient is in AFIB, the more likely they are to remain in AFIB, making early detection desirable. Prompt detection of the onset of AFIB provides an opportunity for therapy during the first 48 hours when expensive antithrombolic treatments may not be necessary because the formation of blood clots has not yet occurred in the atria.
Current methods of detecting AFIB are primarily reliant on the use of continuous ECG recordings. Unfortunately, continuous cardiac monitoring via ECG presents many challenges, including the precise application of a variety of electrodes, an uncomfortable apparatus and cabling, and issues with battery replacement. For many patients this level of acuity is not warranted. It would be desirable to be able to screen for AFIB simply, without requiring electrodes or additional sensors. It would also be desirable to reduce or eliminate false positive alarms in such a system.